| 主权项 |
1. A bridge plug or packer assembly, comprising:
a mandrel; at least one sealing element provided on said mandrel; a pair of backup rings provided on said mandrel on respective sides of said at least one sealing element, each of said pair of backup rings having an engaging ring surface, a ring opening, a ring opening surface facing said ring opening, an outer ring surface and an inner beveled ring surface extending from said engaging ring surface to said ring opening surface and a single spiraled ring groove including an elongated main groove segment extending along a portion of a circumference of said engaging ring surface; a generally curved inner surface groove segment extending from said main groove segment along a portion of said beveled ring surface; an outer surface groove segment extending from said main groove segment along a portion of said outer ring surface; and a pair of pressure-applying elements provided on said mandrel on respective sides of said pair of backup rings, respectively. |
